21742512 has 40 divisors (see below), whose sum is σ = 61275840. Its totient is φ = 6588480.

The previous prime is 21742493. The next prime is 21742571. The reversal of 21742512 is 21524712.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20062 + ... + 21117.

It is an arithmetic number, because the mean of its divisors is an integer number (1531896).

Almost surely, 2^21742512 is an apocalyptic number.

21742512 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21742512 is an abundant number, since it is smaller than the sum of its proper divisors (39533328).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21742512 is a wasteful number, since it uses less digits than its factorization.

21742512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41201 (or 41195 counting only the distinct ones).

The product of its digits is 1120, while the sum is 24.

The square root of 21742512 is about 4662.8866595704. The cubic root of 21742512 is about 279.1064713559.

The spelling of 21742512 in words is "twenty-one million, seven hundred forty-two thousand, five hundred twelve".